1. Field of the Disclosure
The present invention relates generally to electrophotographic image forming devices and more particularly to a toner agitator system for a developer unit for an image forming device.
2. Description of the Related Art
In order to reduce the premature replacement of components traditionally housed within a toner cartridge for an image forming device, toner cartridge manufacturers have begun to separate components having a longer life from those having a shorter life into separate replaceable units. Relatively longer life components such as a developer roll, a toner adder roll, a doctor blade and a photoconductive drum are positioned in one replaceable unit (an “imaging unit”). The image forming device's toner supply, which is consumed relatively quickly in comparison with the components housed in the imaging unit, is provided in a reservoir in a separate replaceable unit in the form of a toner cartridge that mates with the imaging unit. In this configuration, the number of components housed in the toner cartridge is reduced in comparison with traditional toner cartridges.
Toner stored in a reservoir in the toner cartridge is delivered to a toner sump in the imaging unit where the toner is held until it is transferred to a print medium, such as paper, by various imaging components. One or more agitators may be employed in each of the reservoir and the toner sump to mix the stored toner and to break up packed toner. However, it may be difficult for the agitators to reach the entire volume of the toner reservoir and the toner sump to prevent toner from compacting in hard to reach areas. It is often desired that the agitators avoid contact with sensitive imaging components, such as a developer roll in the imaging unit, further limiting the ability to fully agitate the stored toner. Packed toner in the reservoir or toner sump may result in toner starvation where toner does not flow or only partially flows to the print medium even though a sufficient amount of toner remains in the reservoir and/or the toner sump. Accordingly, a toner agitator system that permits ample agitation of stored toner without contacting sensitive imaging components is desired.